Useful Sports Betting Calculations
by Website Staff
Instead of guessing when you place a bet why
not use maths to determine if you have an edge. Every sports
bettor should be familiar with these four sports handicapping
calculations.
Odds Conversion
Most sportsbooks display betting lines in multiple formats
including US odds. Some Asian sportsbooks will not offer this
option, so it is necessary to convert moneyline odds to decimal
or vice versa.
Notice the sum of the teams implied probabilities is 102.4%. The
true odds should add up to 100% but the sportsbook has tacked on
a 2.4% over round.
Explicit Probability
The true odds of a team
winning a game can be estimated by
first calculating the implied probabilities of the team and their
opponent. Than using
the explicit probability calculation to remove the sportsbook
juice or vigorish.
For the following examples assume the moneyline odds on Team A
are -200 which gives them an implied probability of 66.7%
and the moneyline odds on Team B are +180 with an implied
probability of 35.7%.
Chance of Team A winning:
= Team A /(Team A + Team B)
= 66.7%/(66.7%+35.7%)
= 65.1%
Chance of Team B winning:
= Team B /(Team A + Team B)
= 35.7%/(66.7%+35.7%)
= 34.9%
With the juice removed the sum of the team's explicit
probabilities equals 100% and shows the true odds for each team.
Edge
Knowing the true odds, a team has to win a game can
help determine how large of an edge you have over the
sportsbook. If the sportsbook is offering moneyline odds of -200
which is an explicit probability of 65.1% but handicapping reveals the same team has a
70% chance of winning.
Calculate the decimal odds for each probability:
= 1 /65.1% or 1 /0.651 = 1.54
= 1 /70% or 1 /0.7 = 1.43
Calculate the handicappers edge:
= (1.54/1.43) -1 = 0.077 or 7.7%
This information can help sports bettors decide how much to bet.
If the odds offered by the sportsbook have a greater edge than
normal wagers it might be appropriate to increase the size of
the bet.